An integrated circuit (IC) is formed by creating one or more devices (e.g., circuit components) on a semiconductor substrate. Generally, each device is separated from the other devices using an isolation feature such as a shallow trench isolation (STI) structure. Current STI structures are often formed using a process that includes etching and silicon oxide deposition. However, high stress may be induced into an STI structure, such as stress caused in etching the profile corner. The high stress may cause a leakage current that affects the performance of the resulting device. The reduction in size of device geometries used in modern technology nodes may make the leakage issue worse and may also cause other issues, including STI gap filling issues and a degradation of carrier mobility under the high stress caused by the STI process.